EFFICIENCY OF DIFFERENT FAN FILTERS IN MANAGING PARTICULATE MATTER WITHIN NATURALLY VENTILATED CLASSROOM UNDER HAZE CONDITIONS

Abstract

The annual transboundary haze in the Southeast Asia Region has been a perennial problem since 1972. Till date, it remains one of the most publicly identifiable regional environmental crisis with the threehour PSI in Singapore reaching hazardous levels of 401 on June 2013. The current solution of enclosing students in the room encourages the accumulation of CO2 concentration and human bio effluents, increase in relative humidity and temperature, all of which can lead to damaging effects on the children’s health. In view of the worsening haze conditions in Singapore, there is an urgent need to develop an effective and economically feasible ventilation system that can be implemented on a substantial scale to safeguard the health of the children and also to ensure continual operation of the schools in times of haze. The purpose of this dissertation is to advance the development of the Fan Filter Unit specifically in classrooms. Simulated haze through the burning of mosquito coils is also being compared to natural haze to determine the suitability of using it during non-haze seasons. In this field study, MERV 13 and 14 filters are tested at fixed fan speed with performance and comfort parameters such as I/O ratio, air change rate, temperature, relative humidity and sound level to assess the suitability of the FFU in both natural and simulated haze in the context of a classroom. In view of the harmful effects of nanoparticles, particle sizes down to nanoparticles are also being measured and evaluated accordingly. The results from the tests indicates that MERV 13 is superior in terms of particle removal efficiency and air change rate, however, MERV 14 was able to provide better thermal and acoustical comfort. Simulated haze is found to have a higher overall concentration level with different proportion of particle sizes as compared to natural haze. The information provided in this paper serves as a foundation for the further development of an economical haze management system for naturally ventilated classrooms.